In regard to an aging existing pipe, there is a technique of, through the use of an elongated strip-shaped member, forming a pipe-like body inside the existing pipe by a pipe forming device, to rehabilitate the existing pipe based on the pipe-like body. In such a rehabilitation technique, a strip-shaped member overlappingly wound around a drum is fed to a pipe forming device installed inside an existing pipe. In this process, it is necessary to allow the strip-shaped member pullingly unwound from the drum to be fed toward the pipe forming device while being formed in a given helical configuration. This means that the strip-shaped member has to be fed in synchronization with orbital and forward speeds of the pipe forming device. If the feeding of the strip-shaped member is insufficient, the strip-shaped member before reaching the pipe forming device is gradually reduced in helical diameter and increased in helical pitch, which is likely to cause a situation where the strip-shaped member is fully stretched and broken in the end. If the strip-shaped member is excessively fed, the helical pitch thereof is reduced, and the helical diameter thereof is gradually increased, so that the strip-shaped member can be turned upside down. This gives rise to a need to return the strip-shaped member to its original desirable helical configuration, resulting in deterioration in process efficiency.
In order to avoid such situations, it has been necessary to feed the strip-shaped member into the existing pipe, while monitoring and adjusting a feeding state of the strip-shaped member by a plurality of workers deployed on the ground and inside the existing pipe. As illustrated in FIG. 15, in an existing pipe 91, a worker 95 performs, inside a rehabilitation pipe 80, the task of monitoring a state of a strip-shaped member 100, and feeding the strip-shaped member 100 into a pipe forming device 96 while allowing the strip-shaped member 100 to maintaining an adequate helical pitch and diameter in synchronization with orbital and forward speeds of the pipe forming device 96.
However, deployment of many workers leads to an increase in cost. An existing pipe having a small diameter precludes deployment of a worker thereinside. Moreover, tasks inside an existing pipe involve a risk of unexpected events. Therefore, it is desired to make it unnecessary to deploy a worker inside an existing pipe.
For example, a strip-shaped member feed-out device described in Patent Document 1 comprises an inner cylinder supported and fixed with respect to a base, and an outer cylinder rotatably fitted on the inner cylinder. A hydraulic motor for rotationally driving the outer cylinder, and a hydraulic motor for feeding a strip-shaped member, are provided therein. Rotation of the hydraulic motor for rotationally driving the outer cylinder is transmitted to the outer cylinder to cause orbital movement of a feeding mechanism attached to the outer cylinder. In consequence of the orbital movement of the feeding mechanism, orbital movement is imparted to a strip-shaped member.
According to an operation of the hydraulic motor for feeding a strip-shaped member, an inner roller and an outer roller are rotated in mutually opposite directions. A strip-shaped member is fed forwardly while being nipped between the rollers.